The invention relates to a starter system for an internal combustion engine, in particular, for motor vehicles.
It is known that internal combustion engines have to be cranked until they reach the point where they run on their own. To that end, so-called starter systems are used in motor vehicles. These starter systems include a starter motor, supplied by a motor vehicle battery, a reduction gear, and a pinion-engaging assembly. For starting the engine, the starter motor is connected to the motor vehicle battery via a starter switch (ignition switch). Once the starter motor is put in operation, a pinion is made to engage a ring gear disposed on a crankshaft of the engine, so that the engine can be cranked. Since the starter motors have a substantially higher rpm than what is required to crank the engine, these different rotary speeds are adapted via a reduction gear. The reduction gear is typically embodied as a planetary gear, with the sun wheel drivable by the starter motor and the crankshaft operatively connected to the planet wheels.
A crankshaft torque required to crank the engine and a minimum crankshaft rpm depend on engine parameters, such as stroke volume, number of cylinders, compression, friction losses, temperature, and additional loads. Thus a starter system has to be adapted to the parameters of the engine. In particular, there is a need for starter systems with different starting power levels and/or different starting rotary speeds.
In the known starter systems, it is disadvantageous that for the sake of high utilization of installation space, they are embodied in a so-called inter-nested way, and that to adapt the starter power and/or the starting rotary speed of the starter, many different-sized starter systems are needed. Adapting to altered parameters of an engine can be done only by redimensioning or reconstructing the entire starter system.
The starter system of the invention offers the advantage over the prior art that adaptation to engines of different parameters can be done in a simple way. Because the primary components of the starter system are embodied as individual modules and can be expanded variably into starter systems with different parameters, it is simple, beginning with the individual modules, to achieve different starter systems without having to reconstruct the entire starter system.
In a preferred feature of the invention, it is provided that the starter system includes a drive module, a gear module and an electronic module. This makes it possible for the primary components of the starter system to be optimized individually to desired starting parameters, so that the desired starter system with the requisite parameters can be assembled from the existing variously-sized individual modules. It is also preferable for a drive module to be combinable with different gear modules, so that adapting the starter system to a desired crankshaft rpm can be done solely via the gear modules. Thus the same type of drive modules can be combined with the appropriate gear modules. On the other hand, it is equally possible for different crankshaft torques to be attained via drive modules with different power level parameters but the same gear modules.
Overall, it becomes clear that by the modular design of the starter system provided for by the invention, identical component groups can be used for different starter system power level classes. By taking standard sizes into account in the individual component groups, these groups can be accordingly assembled in final form economically, thus reducing both the effort and cost of production. In particular, this also makes for high flexibility in final assembly of the starter system, especially when making a rapid adaptation to altered application requirements of different internal combustion engines.